swf will not play properly. HELP!

Im taking a 2 minute long 720 x 480 avi file and compressing it it to a swf file, using the sorenson sompression suite 3.5 (spark codec). The compression settings are as follows: 320 x 240 frame size, 29.97 fps or 15 fps, @ 200 kbps w/ the 1 pass VBR. The problem Im experiencing is that once the swf is created and posted directly to our company's ftp for client viewing via web browser, the videos appear to play at a much slower rate than I instructed them to. The 29.97 fps video plays entirely in slow motion while the 15 fps video takes almost 17 seconds longer to complete than it should. Why is this happening and how can I fix the problem? The reason Im using a swf to begin with is because we also use a video player (created in Flash MX 2004) for FF and FR functions and it requires swf's. But either way, the files do not play at the rate they should. They play fine on the computer's desktop but once posted to the web they are severely slowed down? Ive tried this on 5 different computers. One on a high speed cable modem and there is no difference b/w any playback- all way too slow!Any help would be greatly appreciated!